Grading machine



Feb. 12 i924. r 1,483,594

C. G. PFEIFFER GRADING MACHINE Filed April 4, 1.922 2 Sheets-Sheet l Ill Charla; x -W97 Feb. 12 1924. 1,483,594

C. G. PFEIFFER- GRADING MACHINE Filed Ap ril 4, 1922 2 Sheets -Sheet 2 INVENTOR:

ATTORNEYS:

Patented Feb. 12, 1924.

PATET CHARLES G. PFIEIFFER, F PHILADELPHIA,

PENNSYLVANIA, ASSIGNOR TO SPECIALTY ENGINEERING COMPANY, OF PHILADELPHIA; PENNSYLVANIA, A CORPORATION OF PENNSYLVANIA.

GRADING MACHINE.

Application filed April 4,

State of Pennsylvania, have invented certain new and useful Improvements in Grading Machines, of which the following is a specification, reference being had to the accompanying drawings.

This invention relates to rotary screening devices for grading materials of a granular or pulverulent nature such as sand, gravel, coal or the like, and more particularly to a power means for operating screening devices of this character.

An object of the invention is to provide a friction drive for rotary screens, deriving power perfectly from an electric motor; and a novel mounting for the screen, whereby the drive maybe readily thrown into operative position or vice versa in a gradual manner without straining the motor and without the use of any form of clutch.

These and other objects are accomplished by what I now regard as the preferred embodiment of my invention from among other possible forms and arrangements comprehended within the spirit of the invention or the scope of the appended claims.

In the accompanying drawings:

Fig. I is a view in top plan of a rotary screen constructed in accordance with my invention.

Fig. II is a view thereof in side elevation with the loading end delineated in section to disclose hidden details.

Fig. III is a view of the screen in end elevation viewing the same from the delivery end; and v V FigrIV is a detail viewin sectionof an eccentric mounting for one end of the drum shaft.

With reference-to the drawings, 10-10 indicates a pair of horizontal frame bars connected at their forward ends by means of a transverse frame bar 11 and at their opposite ends by means of the transverse frame bar 12, the latter being spaced inwardly from the ends of the longitudinal frame members. A third transverse frame bar 13 connects the rear extremities of the longitudinal frame members as clearly shown in Fig. I. Supporting legs 14 are provided at the corners of the rectangular frame structure just described, and their 1922. Serial 1%. 549,569.

relative lengths prescribed so as to lower the rear end-of the frame structure to dispose the latter at a slight angle. A screen drum 15 of conventional type is located within the frame and mounted upon an axial 'sh'aft'16 extending through the drum. The

forward-or upper end of the shaft is formed with a spherical ,terfininal or journal 17 whichvis seated in a socket bearing 18, the latter being mounted centrally of the transverse frame bar 11. The opposite or lower end of the shaft is journalled eccentrically infla bearing sleeve or bushing 18 which, in turn, is'mo'unted for rotation'in an opening formed centrally of the v rear transverse frame bar 12, and 'is formed with an'operating handle 19.

Referring now to the driving mechanism, 20 indicates a short shaft section which is journalledupon and between the end frame" 1 bars 12 and 13 and is disposed substantially parallel to the axis of the drum. A friction pinion 21 is fixedly secured to one end of the shaft 20 which protrudes forwardly and beyond-the frame bar 12, for engagement and cooperation with a friction band 22 applied to therear end of the drum and arranged concentrically relative thereto. Said band 22 also constitutes the end frame member of the drum 15 and is carried by vthe shaft 16 in any suitablemanner, as for instance a spider frame. A relatively large pulley wheel 23 is mounted on the opposite end of the shaft 20 and is driven from smaller pulley wheel 24: mounted on the shaft of an electric motor 25, through the medium of a belt 26. The motor 25 may be supported upon a plate fixed to the frame in any manner found convenient. A hopper 27 of any desired form or size is mounted on the forward transverse frame bar 11 and supplied with a spout 28 to discharge into the upper end of the drum, the graded portion of the aggregate passing through the mesh of theforaminous material forming the walls of the drum, and the residue passing by gravity to the lower end of the latter from which it is discharged. The drum is rotated by virtue of the frictional contact between the driving pinion 21 and the driven band 22; and the rear or lower end of the drum may be shifted laterally to a slight degree suflicient to vary the pressure of engagement between the pinion and band or to completely separate the same so that the liiil motor may run idly at times when rotation of the drum is to be arrested for cleaning or adjustment. This arrangement also permits the motor to be started without load, the drum being subsequently moved slowly into operative engagement with the pinion thereby preventing undue strain upon the motor. The shifting of the drum is accomplished by rocking the handle 19 in one direction or the other as illustrated in Fig. III. The ball and socket journal mounting for the upper end of the drum shaft permits of a slight universal motion occasioned by the eccentric motion of the lower end of the shaft. I

Having thus described my invention, I claim:

1. A grading machine comprising a rotatable screen drum mounted on an axial shaft, one end of said shaft being universally and the other end eccentrically journaled, means for moving the eccentrically journaled end of said axial shaft, and a friction drive operable from a source of power to actuate the screen drum.

2. A grading machine comprising a rotatable screen drum mounted on an axial shaft, one end of said shaft being universally and the other end eccentrically journaled, means for moving the eccentrically journaled end of said shaft, and a friction transmission operable from a source of power for direct co-operation with the screen drum to actuate the same.

3. A grading machine comprising a rotatable screen drum mounted on an axial shaft, one end of said shaft being eccentrically journaled in a bearing sleeve, a power transmission element carried by the screen drum, a co-operative transmission element operable from a source of power to drive the screen drum, and means for partially rotating the aforesaid sleeve to effect co-operative engagement between the transmission elements and vice versa.

f. A grading machine comprising a rotatable screen drum mounted on an axial shaft one end whereof is eccentrically journaled in a bearing sleeve, a friction transmission band on said screen drum, a co-operative friction pinion operable from a source of power to rotate the screen drum, and means for partially rotating the bearing sleeve to effect co-operative engagement between the-friction band and pinion, and vice versa. a p

5. A grading machine comprisinga rotatable screen drum mounted on an axial shaft one end whereof is eccentrically journaled m a bearing sleeve, and driving means therefor adapted for releasable engagement with the screen drum when the latter is eccentrically moved to effect a driving connection to the same.

6. A grading machine comprising a rotatable and eccentrically movable screen drum, a constantly driven power means, and means for eccentrically shifting one end of the screen drum into operative engagement with the power means to effect rotation of said screen drum.

7. A grading machine comprising a rotatable and eccentrically shiftable screen drum, a friction transmission band carried thereby, a co-operative power driven friction transmission pinion, and manually movable means for eccentrically rocking the screen drum to bring the friction band and pinion into contact whereby to effect rotation of said screen drum, and vice versa.

8. A grading machine comprising a rotary drum mounted on an axial shaft, one end of said shaft having a universal bearing and the other end being eccentrically journaled in a bearing sleeve, a friction band on said drum, a cooperative power driven friction pinion, and an operating handle on the bearing sleeve for shifting the grading drum eccentrically to bring the friction band and pinion into .co-operative engagement.

9. A grading machine comprising a rotary drum mounted on an axial shaft, one end of said shaft having a ball and socket bearing and the other end being eccentricallyjournaled in a bearing sleeve, a friction band on said drum, a cooperative power driven friction pinion, and manually operable means for imparting a limited lateral movement to the eccentrically journaled end of the aforesaid shaft whereby the friction band and pinion are moved into and out of cooperative engagement.

10. A grading machine comprising a rotary screen drum mountedon an axial shaft, a universal bearing for one end of said shaft andthe other end being eccentrically journaled in a bearing sleeve, a friction band onthe drum, a cooperative power driven friction pinion, and manually movable means whereby the aforesaid sleeve may be rotated to bring the friction band and pinion into cooperativeengagement.

In testimony whereof, I have hereunto signed my name at Philadelphia, Pennsyl- Vania, this 28th day of March, 1922.

CHARLES G. PFEIFFER.

Witnesses: 7

JAMES H. BELL, E; L. FULLERTON. 

